This invention has an objective to provide a field effect transistor semiconductor which has great adhesiveness between a gate metal and an insulating film defining a gate electrode end and to improve production yield thereof. The field effect transistor semiconductor of this invention comprises a source/drain electrode 6 positioned in a predetermined position in a GaAs substrate 1, a channel region provided in the GaAs substrate 1 and between the source/drain electrodes 6, a gate electrode 11 which is in schottky contact with a part of a channel region and is positioned between the source/drain electrodes 6, and an insulating film 7 which electrically insulates a surface of the GaAs substrate and the gate electrode 11 at both side surfaces of the gate electrode 11. The gate electrode 11 covers a part of the insulating film 7 and the surface of the GaAs substrate serving as the channel region, and a bottom metallic layer 8 contained in the gate electrode 11 is covered with a second metallic layer 9 which is highly adhesive to the insulating film 7.
An integrated circuit having a gate region, a source drain region, and an electrically nonconductive spacer separating the gate region and the source drain region. A local interconnect electrically connects the gate region to the source drain region across the electrically nonconductive spacer. The local interconnect is formed of a semiconducting material reacted with a metal. The local interconnect may be formed by implanting a precursor species into the electrically nonconductive spacer. A metal layer is deposited over at least the electrically nonconductive spacer, and the integrated circuit is heated to form an electrically conductive local interconnect from the metal layer and the precursor species implanted in the electrically nonconductive spacer.
